In recent years, a High-Definition Multimedia Interface (HDMI®) capable of digital high-definition television transmission is becoming common as a communication interface (I/F) for a video device such as a Digital Television (DTV). The HDMI is mainly used for video transmission and can transmit not only a video signal but also an audio signal via a single cable. The HDMI also has a copyright protection mechanism called High-bandwidth Digital Content Protection (HDCP).
The HDMI standard version 1.3 which defines a small connector called type C as well assuming connection to a device such as a digital camera is expected to be implemented on more video devices in the future.
On the other hand, a Universal Serial Bus (USB) is often used as a communication I/F for data transmission/reception of each file or the like. A personal computer (PC) normally has a USB terminal. There is also a growth in the number of DTVs having a USB terminal.
For example, Japanese Patent Laid-Open No. 2004-288141 proposes a memory card capable of using, for example, a USB and a Secure Digital (SD) memory card I/F.